I'm relatively new to home brewing, 4 batches, and have a question on my current attempt. I'm trying for a beer that has good body, soft, full mouth feel, but not over hopped. The recipe ( 5 gal) I have going is as follows:
4 lbs Alexanders pale extract
2 lbs Light DME
1 lb Rice solids
3/4 lb Wheat DME
1/2 lb Malto dextrin
1 oz Cascade 60 min
1 oz Hallertau 15 min
1 oz Saaz 5 min
I have OG of 1. 053, and have just gone to the secondary fermenter. I took a taste and it seems a little sweet. Should I try a dry hop to help balance. I've never dry hopped, so do you just toss the pellets on top? I think I'm a little over my head here and need advice. Comments would be appreciated, both on the recipe and what to do. Thanks!

1.011 isn't the dries beer in the world, but it's pretty low for an extract beer.
That's 79% attenuation, and that's good for most ale yeasts.
What yeast did you use?

If it's seems sweet, it's probably a little low on bitterness. Dry hopping will add hop aroma, but not bitterness. So you could try that, and it will change the character of the beer, but not really fix the issue youn are trying to adress.

I think you'll find that carbonation will give the beer more bite and help balance the beer some more. Hopefully enough to make you happy with this beer.
What kind of beer was this supposed to be?

I used WLP 001 Ale yeast. I am trying for an American Ale style, with the bitterness backed off a little. I've been adjusting the recipe with each batch trying to get a taste that I like. This time I added the malto dextrin and wheat DME. Do you think one of the european based yeasts that give a more malty flavor would be a good change for the next batch?

79% attenuation is toward the high end of what you can expect from 001. See what carbonation does for it, but you may need to up the bitterness a bit the next time you make it.

British yeasts can often improve the maltiness, some Alt yeasts, like 011 can do this as well, but be forewarned that yeasts that highlight the malt often attenuate less. This will leave an identical beer sweeter, so you may need to increase the bitterness to compensate. All-grain brewers often compensate by lowering the mashing temperature.